Synergistic effects of concurrent photodynamic therapy with indocyanine green and chemotherapy in hepatocellular carcinoma cell lines and mouse models.

BACKGROUND: Photodynamic therapy (PDT) using an 808 nm laser irradiation with indocyanine green (ICG) has shown tumoricidal effects in a hepatocellular (HCC) orthotopic xenograft model. Recently, combining PDT with concurrent chemotherapy has shown synergistic outcomes and a better therapeutic effect for cancer treatment. In the present study, we utilized a combination of chemotherapy drugs and PDT using ICG in vitro and in vivo in a patient-derived orthotopic xenograft (PDoX) model. METHOD: We independently performed PDT and chemotherapy with sorafenib or doxorubicin in the Huh-7 and Hep3b cell lines by increasing the sorafenib or doxorubicin concentration and increasing the total energy of 808 nm light. Subsequently, we combined the two treatments to confirm the effects on cell viability. The combination index (CI) was evaluated in vitro, and thereafter, in the HCC PDoX mouse model, 808 nm laser irradiation with intravenously injected ICG and chemotherapy using doxorubicin were performed for twelve days. RESULT: The viability of the Huh-7 and Hep3B cell lines decreased rapidly as the concentration of sorafenib or doxorubicin increased and as the total energy of 808 nm light increased. The cell viability of the Huh-7 and Hep3b cell lines with combined PDT and chemotherapy was less than that with PDT or chemotherapy alone. The CI was <1 in the sorafenib- or doxorubicin-treated Huh-7 and Hep3b cell lines. In the HCC PDoX mouse model, tumor size was markedly decreased, and complete remission achieved compared to that of the single chemotherapy or PDT and control groups. CONCLUSION: The synergistic effect of concurrent PDT and chemotherapy in the HCC cell line and PDoX model was confirmed with no definite adverse effect. Concurrent PDT and chemotherapy could be applied in further preclinical studies.

Guidelines for the Laboratory Diagnosis of Monkeypox in Korea.

While the coronavirus disease 2019 pandemic is ongoing, monkeypox has been rapidly spreading in non-endemic countries since May 2022. Accurate and rapid laboratory tests are essential for identifying and controlling monkeypox. Korean Society for Laboratory Medicine and the Korea Disease Prevention and Control Agency have proposed guidelines for diagnosing monkeypox in clinical laboratories in Korea. These guidelines cover the type of tests, selection of specimens, collection of specimens, diagnostic methods, interpretation of test results, and biosafety. Molecular tests are recommended as confirmatory tests. Skin lesion specimens are recommended for testing in the symptomatic stage, and the collection of both blood and oropharyngeal swabs is recommended in the presymptomatic or prodromal stage.

Guidelines for Mobile Laboratories for Molecular Diagnostic Testing of COVID-19.

With the rapid spread of the coronavirus disease (COVID-19), the need for rapid testing and diagnosis and consequently, the demand for mobile laboratories have increased. Despite this need, there are no clear guidelines for the operation, maintenance, or quality control of mobile laboratories. We provide guidelines for the operation, management, and quality control of mobile laboratories, and specifically for the implementation and execution of COVID-19 molecular diagnostic testing. These practical guidelines are primarily based on expert opinions and a laboratory accreditation inspection checklist. The scope of these guidelines includes the facility, preoperative evaluation, PCR testing, internal and external quality control, sample handling, reporting, laboratory personnel, biosafety level, and laboratory safety management. These guidelines are useful for the maintenance and operation of mobile laboratories not only in normal circumstances but also during public health crises and emergencies.

Update of Guidelines for Laboratory Diagnosis of COVID-19 in Korea.

Korean Society for Laboratory Medicine and the Korea Disease Prevention and Control Agency have announced guidelines for diagnosing coronavirus disease (COVID-19) in clinical laboratories in Korea. With the ongoing pandemic, we propose an update of the previous guidelines based on new scientific data. This update includes recommendations for tests that were not included in the previous guidelines, including the rapid molecular test, antigen test, antibody test, and self-collected specimens, and a revision of the previous recommendations. This update will aid clinical laboratories in performing laboratory tests for diagnosing COVID-19.

Nationwide External Quality Assessment of SARS-CoV-2 Molecular Testing, South Korea.

External quality assessment (EQA) is essential for ensuring reliable test results, especially when laboratories are using assays authorized for emergency use for newly emerging pathogens. We developed an EQA panel to assess the quality of real-time reverse transcription PCR assays being used in South Korea to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). With the participation of 23 public health organization laboratories and 95 nongovernmental laboratories involved in SARS-CoV-2 testing, we conducted qualitative and semiquantitative performance assessments by using pooled respiratory samples containing different viral loads of SARS-CoV-2 or human coronavirus OC43. A total of 110 (93.2%) laboratories reported correct results for all qualitative tests; 29 (24.6%) laboratories had >1 outliers according to cycle threshold values. Our EQA panel identified the potential weaknesses of currently available commercial reagent kits. The methodology we used can provide practical experience for those planning to conduct evaluations for testing of SARS-CoV-2 and other emerging pathogens in the future.

Near-infrared phototherapy for patient-derived orthotopic xenograft model of hepatocellular carcinoma in combination with indocyanine green.

BACKGROUND: Hepatocellular carcinoma notably takes up and retains indocyanine green (ICG). Here, we investigated whether patient-derived orthotopic xenograft of hepatocellular carcinoma could accumulate ICG and show full remission via phototherapy. METHODS: NIR light and ICG were tested for cytotoxicity in cancerous cell lines (Huh-7, Hep3B). Patient-derived orthotopic xenograft (PDoX) mice were subjected to phototherapy comprising of daily NIR exposure (0.5-1.75 W/cm2) and intravenous injection of ICG (5-20 mg/kg2). Moreover, NIR laser was flashed on individual mouse until hepatocellular carcinoma completely loss the fluorescence, as determined by NIR camera. RESULTS: Cytotoxicity increased in response to the input energy, but insufficient energy (< 150 joule/cm2) was irresponsive at all irradiances. NIR irradiance in the range of 0.5-1.75 W/cm2 took 5-7 days to elicit complete remission from PDoX mice in combination with 20 mg/kg ICG. In contrast, phototherapy could completely ablate hepatocellular carcinoma at 5-15 mg/kg ICG. CONCLUSIONS: ICG could potentiate the tumoricidal ability of NIR light in a dose-dependent manner, and vice versa. Regardless of ICG dosage, however, phototherapy treated group showed a relatively high survival rate compared to the non-treated group. Notably, real-time phototherapy could halve the effective ICG dosage for full remission of deep-seated tumor.

Guidelines for Laboratory Diagnosis of Coronavirus Disease 2019 (COVID-19) in Korea.

The outbreak of coronavirus disease 2019 (COVID-19), which began in December 2019, is still ongoing in Korea, with >9,000 confirmed cases as of March 25, 2020. COVID-19 is a severe acute respiratory syndrome Coronavirus 2 (SARS-CoV-2) infection, and real-time reverse transcription-PCR is currently the most reliable diagnostic method for COVID-19 around the world. Korean Society for Laboratory Medicine and the Korea Centers for Disease Prevention and Control propose guidelines for diagnosing COVID-19 in clinical laboratories in Korea. These guidelines are based on other related domestic and international guidelines, as well as expert opinions and include the selection of test subjects, selection of specimens, diagnostic methods, interpretation of test results, and biosafety.

Association between Abdominal Obesity and Oxidative Stress in Korean Adults.

BACKGROUND: Obesity causes several changes in the body and is associated with both inflammation and oxidative stress. However, the relationship between abdominal obesity, diacron-reactive oxygen metabolites (d-ROMs), and biological antioxidant potential (BAP) levels in Korean adults has not yet been proved. The aim of this study was to evaluate the association between d-ROMs, BAP levels, and abdominal obesity in the Korean adult population using clinical data. METHODS: A total of 2,367 individuals, aged 18-86 years, were identified from health check-up examination records at a university hospital, between January 2015 and August 2016. Clinical and biochemical parameters, including waist circumference, lipid profile, alcohol drinking status, and smoking status, were investigated. Oxidative stress levels, viz., d-ROM concentration and antioxidant capacity, viz., BAP, were measured. RESULTS: Subjects with abdominal obesity presented significantly higher levels of d-ROMs compared to those with a normal waist circumference (P<0.001). After adjusting for age, sex, alcohol drinking status; smoking status; and triglyceride, low-density lipoprotein levels were found to have a significant positive correlation with abdominal obesity (P<0.001). BAP did not significantly correlate with abdominal obesity. CONCLUSION: We observed a positive association between abdominal obesity and d-ROM concentration. This result indicates that abdominal obesity can increase oxidative stress and may affect the pathways involved in obesity, such as the inflammatory pathway. Such correlation analyses were helpful in revealing the causes, as well as methods to reduce, oxidative stress.

Signal to noise ratio of upgraded imaging bolometer for KSTAR.

An InfraRed imaging Video Bolometer (IRVB) was installed on KSTAR in 2012 having a ∼2 µm × 7 cm × 9 cm Pt foil blackened with graphite and a 5 mm × 5 mm aperture located 7.65 cm from the foil with 16 × 12 channels and a time resolution of 10 ms. The IR camera was an Indigo Phoenix (InSb, 320 × 256 pixels, 435 fps, <25 mK). In 2017, the IRVB was upgraded by replacing the IR camera with a FLIR SC7600 (InSb, 640 × 512 pixels, 105 fps, <25 mK). The aperture area was reduced by approximately half to 3.5 mm × 3.5 mm, and the number of channels was quadrupled to 32 × 24. A synthetic image derived using the projection matrix for the upgraded IRVB from a Scrape Off Layer Plasma Simulator (SOLPS) model with 146 kW of total radiated power had a maximum signal of 7.6 W/m2 and a signal to noise ratio (SNR) of 11. Experimental data for a plasma with parameters similar to the SOLPS model (total radiated power of 158 kW) had a maximum signal of 12.6 W/m2 and noise equivalent power density (SNR) of 0.9 W/m2 (14).

Development of a neural network technique for KSTAR Thomson scattering diagnostics.

Neural networks provide powerful approaches of dealing with nonlinear data and have been successfully applied to fusion plasma diagnostics and control systems. Controlling tokamak plasmas in real time is essential to measure the plasma parameters in situ. However, the χ2 method traditionally used in Thomson scattering diagnostics hampers real-time measurement due to the complexity of the calculations involved. In this study, we applied a neural network approach to Thomson scattering diagnostics in order to calculate the electron temperature, comparing the results to those obtained with the χ2 method. The best results were obtained for 103 training cycles and eight nodes in the hidden layer. Our neural network approach shows good agreement with the χ2 method and performs the calculation twenty times faster.

Development of a particle injection system for impurity transport study in KSTAR.

A solid particle injection system is developed for KSTAR. The system has a compact size, compatibility with a strong magnetic field and high vacuum environment, and the capability to inject a small amount of solid particles with a narrow injection angle. The target flight-distance of 10 cm has been achieved with a particle loss rate of less than 10%. Solid impurity particles such as tungsten and carbon will be injected by this system at the midplane in KSTAR. The impurity transport feature will be studied with a soft X-ray array, a vacuum ultra-violet diagnostic, and Stand Alone Non-Corona code.

A strategic plan for the second phase (2013-2015) of the Korea biobank project.

The Korea Biobank Project (KBP) was led by the Ministry of Health and Welfare to establish a network between the National Biobank of Korea and biobanks run by university-affiliated general hospitals (regional biobanks). The Ministry of Health and Welfare started the project to enhance medical and health technology by collecting, managing, and providing researchers with high-quality human bioresources. The National Biobank of Korea, under the leadership of the Ministry of Health and Welfare, collects specimens through various cohorts and regional biobanks within university hospitals gather specimens from patients. The project began in 2008, and the first phase ended in 2012, which meant that there needed to be a plan for the second phase that begins in 2013. Consequently, professionals from within and outside the project were gathered to develop a plan for the second phase. Under the leadership of the planning committee, six working groups were formed to formulate a practical plan. By conducting two workshops with experts in the six working groups and the planning committee and three forums in 2011 and 2012, they have developed a strategic plan for the second phase of the KBP. This document presents a brief report of the second phase of the project based on a discussion with them. During the first phase of the project (2008-2012), a network was set up between the National Biobank of Korea and 17 biobanks at university-affiliated hospitals in an effort to unify informatics and governance among the participating biobanks. The biobanks within the network manage data on their biospecimens with a unified Biobank Information Management System. Continuous efforts are being made to develop a common standard operating procedure for resource collection, management, distribution, and personal information security, and currently, management of these data is carried out in a somewhat unified manner. In addition, the KBP has trained and educated professionals to work within the biobanks, and has also carried out various publicity promotions to the public and researchers. During the first phase, biospecimens from more than 300,000 participants through various cohorts and biospecimens from more than 200,000 patients from hospitals were collected, which were distributed to approximately 600 research projects. The planning committee for the second phase evaluated that the first phase of the KBP was successful. However, the first phase of the project was meant to allow autonomy to the individual biobanks. The biobanks were able to choose the kind of specimens they were going to collect and the amount of specimen they would set as a goal, as well as being allowed to choose their own methods to manage their biobanks (autonomy). Therefore, some biobanks collected resources that were easy to collect and the resources needed by researchers were not strategically collected. In addition, there was also a low distribution rate to researchers outside of hospitals, who do not have as much access to specimens and cases as those in hospitals. There were also many cases in which researchers were not aware of the KBP, and the distribution processes were not set up to be convenient to the demands of researchers. Accordingly, the second phase of the KBP will be focused on increasing the integration and cooperation between the biobanks within the network. The KBP plans to set goals for the strategic collection of the needed human bioresources. Although the main principle of the first phase was to establish infrastructure and resource collection, the key objective of the second phase is the efficient utilization of gathered resources. In order to fully utilize the gathered resources in an efficient way, distribution systems and policies must be improved. Vitalization of distribution, securing of high-value resource and related clinical and laboratory information, international standardization of resource management systems, and establishment of a virtuous cycle between research and development (R&D) and biobanks are the four main strategies. Based on these strategies, 12 related objectives have been set and are planned to be executed.

The combination of real-time PCR and HPLC for the identification of non-tuberculous mycobacteria.

We used HPLC and AdvanSure real-time PCR (LG Life Sciences, Korea) to retrospectively analyze non-tuberculous mycobacteria (NTM) in 133 clinical specimens. The specimens were culture-positive for NTM and the HPLC method identified 130 strains of mycobacteria from the cultures (97.7%) at the species level. Among the isolates, 48 Mycobacterium. kansasii (36.1%), 39 M. intracellulare (29.3%), 17 M. avium (12.8%), 16 M. abscessus (12.0%), 6 M. fortuitum (4.5%), 2 M. szulgai (1.5%), 2 M. gordonae (1.5%), and 3 unclassified NTM strains (2.3%) were identified. The real-time PCR assay identified 60 NTM-positive specimens (45.1%), 65 negative specimens (48.9%), and 8 M. tuberculosis (TB)-positive specimens (6.0%). The real-time PCR assay is advantageous because of its rapid identification of NTM. However, in our study, the real-time PCR assay showed relatively low sensitivity (45.1%) when using direct specimens including sputum and bronchoalveolar lavage (BAL) fluid. HPLC is useful as it discriminates NTM at the species level, although it is time-consuming and requires specific equipment and technical expertise. A combination of both methods will be helpful for the rapid and accurate identification of mycobacteria in clinical laboratories.

Severe dapsone hypersensitivity syndrome in a child.

Dapsone (4,4'-diaminodiphenylsulfone, DDS), a potent anti-inflammatory agent, is widely used in the treatment of leprosy and several chronic inflammatory skin diseases. Dapsone therapy rarely results in development of dapsone hypersensitivity syndrome, which is characterized by fever, hepatitis, generalized exfoliative dermatitis, and lymphadenopathy. Here, we describe the case of an 11-year-old Korean boy who initially presented with high fever, a morbilliform skin rash, generalized lymphadenopathy, hepatosplenomegaly, and leukopenia after 6 weeks of dapsone intake. Subsequently, he exhibited cholecystitis, gingivitis, colitis, sepsis, aseptic meningitis, disseminated intravascular coagulation, syndrome of inappropriate antidiuretic hormone secretion, pneumonia, pleural effusions, peritonitis, bronchiectatic changes, exfoliative dermatitis, and acute renal failure. After 2 months of supportive therapy, and prednisolone and antibiotic administration, most of the systemic symptoms resolved, with the exception of exfoliative dermatitis and erythema, which ameliorated over the following 4 months. Agranulocytosis, atypical lymphocytosis, aseptic meningitis, and bronchiectatic changes along with prolonged systemic symptoms with exfoliative dermatitis were the most peculiar features of the present case.

Identification of clinical biomarkers for pre-analytical quality control of blood samples.

BACKGROUND: Pre-analytical conditions are key factors in maintaining the high quality of biospecimens. They are necessary for accurate reproducibility of experiments in the field of biomarker discovery as well as achieving optimal specificity of laboratory tests for clinical diagnosis. In research at the National Biobank of Korea, we evaluated the impact of pre-analytical conditions on the stability of biobanked blood samples by measuring biochemical analytes commonly used in clinical laboratory tests. METHODS: We measured 10 routine laboratory analytes in serum and plasma samples from healthy donors (n = 50) with a chemistry autoanalyzer (Hitachi 7600-110). The analyte measurements were made at different time courses based on delay of blood fractionation, freezing delay of fractionated serum and plasma samples, and at different cycles (0, 1, 3, 6, 9) of freeze-thawing. Statistically significant changes from the reference sample mean were determined using the repeated-measures ANOVA and the significant change limit (SCL). RESULTS: The serum levels of GGT and LDH were changed significantly depending on both the time interval between blood collection and fractionation and the time interval between fractionation and freezing of serum and plasma samples. The glucose level was most sensitive only to the elapsed time between blood collection and centrifugation for blood fractionation. Based on these findings, a simple formula (glucose decrease by 1.387 mg/dL per hour) was derived to estimate the length of time delay after blood collection. In addition, AST, BUN, GGT, and LDH showed sensitive responses to repeated freeze-thaw cycles of serum and plasma samples. CONCLUSION: These results suggest that GGT and LDH measurements can be used as quality control markers for certain pre-analytical conditions (eg, delayed processing or repeated freeze-thawing) of blood samples which are either directly used in the laboratory tests or stored for future research in the biobank.

Lung infection caused by Mycobacterium riyadhense confused with Mycobacterium tuberculosis: the first case in Korea.

A slowly growing, non-chromogenic mycobacterial strain was isolated from sputum and bronchial lavage fluid samples of a patient presenting with productive cough, blood-tinged sputum, low-grade fever, and weakness. A positive acid-fast bacilli sputum smear result prompted the initiation of an anti-tuberculosis regimen. Multiplex real-time PCR showed a negative result for Mycobacterium tuberculosis complex and a positive result for nontuberculous mycobacteria. The DNA chip test confirmed this organism as a member of the genus Mycobacterium, but could not specify the species. Interestingly, the mycolic acid patterns obtained by HPLC nearly overlapped with those of M. simulans. The sequences of the Mycobacterium 16S rRNA gene and 16S-23S internal transcribed spacer region were unique and were found to have 100% similarity with those of M. riyadhense. After a review of the literature, we report this case as the first Korean case of M. riyadhense lung infection.

Identification and characterization of a novel ß-galactosidase from Victivallis vadensis ATCC BAA-548, an anaerobic fecal bacterium.

Victivallis vadensis ATCC BAA-548 is a Gram-negative, anaerobic bacterium that was isolated from a human fecal sample. From the genomic sequence of V. vadensis, one gene was found to encode agarase; however, its enzymatic properties have never been characterized. The gene encoding the putative agarase (NCBI reference number ZP_01923925) was cloned by PCR and expressed in E. coli Rosetta-gami by using the inducible T(7) promoter of pET28a(+). The expressed protein with a 6×His tag at the N-terminus was named His6-VadG925 and purified as a soluble protein by Ni(2+)-NTA agarose affinity column chromatography. The purification of the enzyme was 26.8-fold, with a yield of 73.2% and a specific activity of 1.02 U/mg of protein. The purified His6-VadG925 produced a single band with an approximate MW of 155 kDa, which is consistent with the calculated value (154,660 Da) including the 6×His tag. Although VadG925 and many of its homologs were annotated as agarases, it did not hydrolyze agarose. Instead, purified His(6)-VadG925 hydrolyzed an artificial chromogenic substrate, p-nitrophenyl-ß-D-galactopyranoside, but not p-nitrophenyl-α-D-galactopyranoside. The optimum pH and temperature for this ß-galactosidase activity were pH 7.0 and 40°C, respectively. The K(m) and V(max) of His6-VadG925 towards p-nitrophenyl-ß-D-galactopyranoside were 1.69 mg/ml (0.0056 M) and 30.3 U/mg, respectively. His6-VadG925 efficiently hydrolyzed lactose into glucose and galactose, which was demonstrated by TLC and mass spectroscopy. These results clearly demonstrated that VadG925 is a novel ß-galactosidase that can hydrolyze lactose, which is unusual because of its low homology to validated ß-galactosidases.

Impact of attachment, temperament and parenting on human development.

The purpose of this review is to present the basic concepts of attachment theory and temperament traits and to discuss the integration of these concepts into parenting practices. Attachment is a basic human need for a close and intimate relationship between infants and their caregivers. Responsive and contingent parenting produces securely attached children who show more curiosity, self-reliance, and independence. Securely attached children also tend to become more resilient and competent adults. In contrast, those who do not experience a secure attachment with their caregivers may have difficulty getting along with others and be unable to develop a sense of confidence or trust in others. Children who are slow to adjust or are shy or irritable are likely to experience conflict with their parents and are likely to receive less parental acceptance or encouragement, which can make the children feel inadequate or unworthy. However, the influence of children's temperament or other attributes may be mitigated if parents adjust their caregiving behaviors to better fit the needs of the particular child. Reflecting on these arguments and our childhood relationships with our own parents can help us develop the skills needed to provide effective guidance and nurturance.

A survey of diabetic educators and patients for the revision of korean food exchange lists.

BACKGROUND: Food exchange lists are one of the main methods of nutritional education. However, Korean food exchange lists have not been revised since 1994. Therefore, we surveyed the opinions of diabetes educators and patients with diabetes regarding the need for revision of the current food exchange lists. METHODS: For two weeks beginning on 10 March 2008, a 12-item questionnaire regarding the opinion and need for revision of the current food exchange lists was e-mailed to diabetes educators nationwide. Another 15-question survey was administered to patients with diabetes in 13 hospitals located in the Seoul and Gyeonggi regions of Korea. RESULTS: We obtained survey responses from 101 diabetes educators and 209 patients; 65 (64.3%) of the educators answered that the current food exchange lists should be revised. The items that needed revision were the glycemic index, addition of new foods and reaffirmation of exchange standard amounts. The patients demanded specific education about choosing appropriate foods, a balanced meal plan, proper snacks, and dining intake. CONCLUSION: Our survey results demonstrate the need to revise the Korean food exchange lists. This process should focus on glycemic index, the addition of new foods and reconfirmation of one exchange reference unit.

Epidemiology and clinical long-term outcome of childhood aplastic anemia in Korea for 15 years: retrospective study of the Korean Society of Pediatric Hematology Oncology (KSPHO).

PURPOSE: Aplastic anemia (AA) is a rare hematologic disease characterized by pancytopenia and hypocellular marrow. The Korean Society of Pediatric Hematology Oncology investigated retrospectively the incidence, survival, and transfusion independency according to treatment strategies in AA. METHODS: All the questionnaires were sent to members for medical records. We collected and analyzed 702 available data. RESULTS: The male and female ratio was 1.2, and the median age at diagnosis was 9.3 years. The annual incidence of Korean children with AA was 5.16 per million per year. Constitutional anemia was diagnosed in 44 children. In acquired AA, causes were identified in 39 children. Severe AA (SAA) at initial diagnosis was more common than nonsevere AA. The overall survival was 47.8% with supportive care, 68.1% with immunosuppressive therapy (IST), and 81.8% with hematopoietic stem cell transplantation. In IST, response rate was 65.7%, and relapse rate after response was 54.4% within a median of 23.0 months. The factors with overall survival were severity of disease in supportive care, severity and response in IST, donor type, graft failure, and posttransplant events in hematopoietic stem cell transplantation. CONCLUSIONS: Long-term outcome in AA was dependent on treatment strategies. These Korean results may help research and prospective international clinical trials for childhood AA.